The move by Japan's parliament to pass bills which strengthen the military is considered controversial in a country that renounced the right to wage war more than half a century ago.
By Charles Scanlon
BBC Tokyo correspondent
The three bills, which were passed by the lower house of parliament by an overwhelming majority, will give the government more powers to respond to an attack on Japan.
Japanese governments have long talked about changing the military law.
It was the terror attacks in the United States and the threat from North Korea that finally gave it the impetus.
The Defence Minister, Shigeru Ishiba, was exultant.
Japan's military is one of the world's most modern, but it is emasculated
"This issue has been debated for the last 26 years. It's remarkable that it was passed with a 90% majority. In the past it was so hard to get military related bills approved, there was always a big fight. I'd like to express my admiration for all those responsible," he said.
The government argues that red tape and arcane rules would prevent the military from responding effectively to an external threat.
Tanks are currently required to wait at traffic lights, and military commanders need permission from regional governors for any action.
The new bills will give the central government the power to take control during an emergency, and the armed forces will be allowed to commandeer civilian land and property and move more freely.
Left-wing parties have said that the legislation would undermine Japan's standing as a pacifist nation - enshrined in the post-war constitution.
But the growing nuclear and missile threat from North Korea has led to a radical shift in opinion.
Calls are growing to further enhance Japan's military capabilities, according to Gerald Curtis, visiting professor from Columbia University.
Because of the North Korean threat (Japanese liberals) have swung to the other extreme and are very hawkish. And so there's a lot of commonality between the mood among the conservative circles here and the mood in Washington
Gerald Curtis, Columbia University
"You have the emergence of a group of Japanese that are very similar to the so-called neo-conservatives around George Bush.
"There are these Japanese neo-conservatives - people who used to be fairly liberal, didn't talk much about military power and so on... now, because of the North Korean threat, (they) have swung to the other extreme and are very hawkish. And so there's a lot of commonality between the mood among the conservative circles here and the mood in Washington," Mr Curtis said.
Liberal opinion remains deeply suspicious of the armed forces - a legacy of the 1930s, when a powerful military led Japan into a disastrous war.
But the main opposition Democratic Party overcame strong objections within its own ranks and agreed to back the bills, after insisting on further guarantees that civil rights would not be compromised.
That marks a big change after years of political deadlock over the role and capability of the military.
The debate is already moving on, with some calling for Japan to go nuclear if North Korea refuses to give up its nuclear programme.
That's not likely any time soon, but Ichita Yamamoto of the ruling Liberal Democratic Party said other steps could be taken.
Neighbouring North Korea is making Japan nervous
"Even if we cannot possess a nuclear weapon, we can strengthen the capability of Japan's civil defence forces. For instance, at present, no fighter has the ability to attack missile bases on the soil of North Korea," he said.
Mr Yamamoto and others have noted that Japan needs a credible military deterrent including long range attack aircraft and Tomahawk missiles.
That would transform Japan's purely defensive posture - maintained for half a century - and would set alarm bells ringing across the region.